WO2024074453A1

WO2024074453A1 - Method for dyeing cotton-containing textile material

Info

Publication number: WO2024074453A1
Application number: PCT/EP2023/077238
Authority: WO
Inventors: Yogesh E. BHOGE; Santosh SURVE; Rasika Chatterjee
Original assignee: Huntsman Textile Effects (Germany) Gmbh
Priority date: 2022-10-03
Filing date: 2023-10-02
Publication date: 2024-04-11

Abstract

The present invention relates to a method for dyeing cotton-containing textile material, wherein the textile material is treated with a liquor containing at least one reactive dye, at least one surfactant, at least one silicone oil and water.

Description

METHOD FOR DYEING COTTON-CONTAINING TEXTILE MATERIAL

Description

The present invention relates to a method for dyeing cotton-containing textile material, wherein the textile material is treated with a liquor containing at least one reactive dye, at least one silicone oil, at least one surfactant and water, to dyed cotton-containing textile material obtained according to such a method.

The dyeing and finishing of textiles consumes large amounts of dyes and freshwater every year, and also generates large amounts of wastewater [see references 1 to 3].

These effluents have serious carcinogenic effects on aquatic biota and humans [4,5]. To solve this problem, governments are increasingly focusing on the implementation of environmental regulations. In this context, new technologies are being developed to improve dye quality/fixation and reduce waste disposal. As a result, the industry is looking for alternative ways to overcome the above problems, in particular attempts are being made to modify the dyeing machines [6], the dye chemistry [7-9] and the cotton substrate [10-15].

Among all new dyeing technologies [16,17], dyeing with organic solvents for reactive dyeing has become very popular. Various organic solvent dyeing medium have been developed to reduce the hydrolysis of reactive dyes and the amount of waste. Generally, non-nucleophilic organic solvents such as DMSO [18], DMAc [19], hexane [20], ethanol [21] and ethyl octanoate [22] have been chosen as dyeing media. However, there are several limitations to solvent dyeing, such as the difficulty of achieving zero emission or 100% solvent recycling. In addition, most organic solvents have low flash points, high volatility, or other adverse properties. Supercritical CO₂ (ScCO₂)-cotton dyeing technology has also been discussed as an alternative dyeing medium, although this might require additional swelling agents and extensive structural modifications to commercial reactive dyes to achieve strong colour depth [23,24].

The most successful attempt that could be considered for industrial scale implementation is the cationization of cotton with 3-chloro-2- hydroxypropyltrimethylammonium chloride (CHPTAC). It is well established in the literature that CHPTAC has higher dye fixation efficiency without affecting the environment [25-29]. However, the industry has yet to embark on this path because the application of CHPTAC to cotton must be done in cold-pad-batch, pad-steam, pad-dry-cure, and pad-bake processes. However, these processes require a batch time of 16 to 24 hours; moreover, this process is best suited for woven goods [30,31].

In the non-aqueous dyeing technique, D5 medium [32-35], spent cooking oil [36] and cottonseed oil [37] are used as dyeing medium for dyeing cotton fabrics. In this process, the dye fixation is increased with the help of the external phase, thus reducing the emission of pollutants. An advantage here is that no salt is required for dyeing. However, this technique also has some practical limitations. Since spent cooking oils, hydrocarbons and D5 media are used for dyeing, during dyeing at high temperatures and under basic/acidic conditions, the used cooking oils may saponify or become rancid. In addition, the use of hydrocarbons and D5 medium for dyeing is restricted due to handling and toxological reasons.

Some of the prior dyeing process for cotton fibers utilizes a large amount of water, electrolyte, such as NaCI or Na₂SO₄ was added gradually in batches to promote the adsorption of dyes and chemicals during dyeing process. However, owing to the dissociation of hydroxyl groups on cotton fibers, slightly negative surface charges are easily produced when cotton comes in contact with water, leading to electrostatic repulsion between the dye and the fibers, to suppress this repulsion and improving the affinity of the reactive dye towards the fibers, huge amounts of salts were required.

Conventional dyeing processes for cotton fibers usually utilize a large amount of dyeing liquors includes fresh water with high liquor ratio. Further, these processes are relatively time-consuming and associated with a considerable amount of liquid waste.

This leads to a potential hazard for the environment and high ETP process costs.

Water scarcity and increased environmental awareness created a need to develop and adopt water free dyeing technologies.

Moreover some of the prior art processes are and unfriendly in their handling and harmful to the environment and are further associated with practical limitations.

Therefore, a dyeing system should be eco-friendly, cost-effective and safe to be suitable to replace the conventional aqueous system. In this context, oils would be a suitable alternative dyeing medium, as they are safe, recycled and has multiple reuse. Due to the fact that the heat capacity of oils is lower than that of water, less energy would be consumed to reach the same dyeing temperature and consequently the process would be more energy efficient. However, the use of oil as a dyeing medium is also associated with several problems, firstly dyes do not dissolve in oil and secondly oil and water are not miscible. Further, the dyeing process often requires high temperatures that can cause oils to become rancid and the dyeing process involves acidic and basic conditions that can saponify the fatty oils.

There is thus a need for overcoming the defect of the prior art.

In particular, there is a need for a dyeing method that results in good all-round fastness properties, such as, good fastness, to rubbing, to wetting, to wet rubbing, to washing, to water, to sea water and to perspiration, are obtained. The washing fastness properties, especially, have very good values. It is possible, to reduce the total duration of dyeing process which saves the energy also. Since the process according to the invention recycle the dyeing media and will be used up to multiple times, hence water used in the procedure is approximately 80% lower than in the conventional process.

It has now been surprisingly found, that a majority of water in a dyeing media for dyeing cotton can be replaced by silicone oil as a dyeing media, hence fresh water used in the process can be significantly reduced by up to 85%. In addition, the use of electrolytes such as NaCI or Na₂SO₄ may be avoided.

The dye solution may be easily dispersed in oil dyeing media with the help of a surfactant. The use of a surfactant may solve the problems of immiscibility of dye and water with oil. This drastically increased the chemical potential of the dyes in the dyeing medium, so that dye fixation could be increased and waste discharges could be minimized.

The proposed dyeing technique may reduce the time cycle, electrolytes, and energy with less consumption of water. The dyeing medium may be reused and may be recycled, which reduces the liquid waste pollutants.

Hence, the instant invention relates to a method for dyeing cotton-containing textile material, wherein the textile material is treated with a liquor containing at least one reactive dye, at least one silicone oil, at least one surfactant and water, and to dyed cotton-containing textile material obtained according to such a method.

Dyeing with this method, results in good all-round fastness properties, such as, good fastness, to rubbing, to wetting, to wet rubbing, to washing, to water, to sea water and to perspiration, are obtained. The washing fastness properties, especially, have very good values. It is also possible, to reduce the total duration of the dyeing process which saves the energy. Since in the process according to the invention the dyeing media may be recycled and used up to multiple times, the water used in the liquor can be approximately 80% lower than in the conventional process. In the instant description and claims, the term "consists essentially of" followed by one or more characteristics, means that may be included in the process or the material of the invention, besides explicitly listed components or steps, components or steps that do not materially affect the properties and characteristics of the invention.

The expression "comprised between X and Y" includes boundaries, unless explicitly stated otherwise. This expression means that the target range includes the X and Y values, and all values from X to Y.

Throughout the description and claims of this specification, the words "comprise" and "contain" and variations of the words, for example "comprising" and "comprises", mean "including but not limited to", and do not exclude other moieties, additives, components, integers or steps. Moreover, the singular encompasses the plural unless the context otherwise requires: in particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

Where upper and lower limits are quoted for a property, for example for the concentration of a component, then a range of values defined by a combination of any of the upper limits with any of the lower limits may also be implied.

The instant invention relates to a method for dyeing cotton-containing textile material, wherein the textile material is treated with a liquor containing at least one reactive dye, at least one silicone oil, at least one surfactant and water.

The method for dyeing cotton-containing textile material preferably comprises or is an exhaust method.

The process according to the invention is suitable for dyeing fiber materials based on cotton and can be used for dyeing 100% cotton fabrics or fabrics comprising cotton as well as other materials. In one embodiment, the inventive method comprising the steps, preferably in that order:

(a) incubating the textile material with the liquor containing at least one reactive dye, the at least one silicone oil, the at least one surfactant and water,

(b) heating the mixture of step (a), preferably to a temperature of 60 to 100 °C.

In one embodiment, the at least one surfactant is selected from butylpolyalkylene glycol copolymers or C12-C14 alcohol based EO molecules , preferably block copolymers in which the central polypropylene glycol group is flanked by two polyethylene glycol groups.

In one embodiment, the above mentioned surfactants can be used in combination.

In one embodiment, several surfactants, preferably two or three surfactants, are used.

In one embodiment, the at least one surfactant is present in an amount of 1 to 5 g/l, preferably 2 to 4 g/l.

Preferably, the temperature during the incubation in step (a) is in the range of 20 to 40 °C.

The incubation step (a) is preferably carried out for 5 to 15 minutes.

The heating step (b) preferably comprises heating to 60 to 100 °C, in particular to 70 to 90 °C such as about 80°C.

The heating step (b) is preferably carried out for 20 to 40 minutes.

Without being bound to that theory it can be hypothesized that the dyeing process can be divided in three different steps. In step I, the temperature is lower, and the dye molecules are continuously adsorbed on to the surface of fabric. In step II the temperature is increased so that there is equilibrium in adsorption and desorption, e.g. at temperatures from 40°C to 70°C, of dyes form the fiber surface. In step III, e.g. at 60°C, after addition of alkali there is an increase in fixation between fiber molecular chain and reactive dyes hence the dye uptake efficiency increases.

The at least one silicone oil constituted the major replacement for water and is thus a decisive contributor in the dyeing process. Silicone oil, in particular nonfunctional silicone oil, revels good synergism between acidic and basic conditions at high temperature. Also, it exhibits excellent levelness and color strength and has a benefit of reusability. Further, the use of different media like hydrocarbon, solvents and different fatty acids (oil) are unfriendly to handle and harmful to environment. Further a dyeing process that involves acidic and basic conditions could lead to saponification of the fatty oils and rancidity of fatty oils at high temperature.

In one embodiment, the inventive method further comprising the following steps, preferably in that order and preferably after above defined steps (a) and (b):

(c) addition of alkali and

(d) neutralizing and washing the textile material.

The addition of alkali is preferably carried out using a carbonate, such as sodium carbonate or potassium hydroxide.

The addition of alkali is preferably carried out at a temperature, which is lower than the temperature in step (b).

The addition of alkali is preferably carried out at a temperature of 50 to 70 °C.

The addition of alkali is preferably carried out for 10 to 20 minutes.

In one embodiment, the cotton-containing textile material may be washed between the steps (b) and (c), preferably using hot water.

After the addition of alkali, the dyeing mixture is preferably neutralized to a pH of about 3 to 5. The neutralization might be carried out using a mild acid, such as acetic acid.

The neutralization is preferably carried out at a temperature of 30 to 40 °C.

After neutralization, the dyed cotton-containing textile material is soaped and washed, preferably cold washed, preferably using water.

After washing, the cotton-containing textile material may be dried using any conventionally known drying method such as heating, e.g. to about 60 to 80 °C, preferably for 30 to 40 minutes.

In one embodiment, the method according to the invention is characterized in that the weight ratio of at least one silicone oil to water is from 75:25 to 90: 10, or from 80:20 to 90: 10, preferably from 85: 15 to 90: 10.

Such a weight ratio has the advantage that a high silicone oil ratio lowers down the content of water and auxiliaries used in dyeing system and exhibits high dye uptake increase in high depth which results in increased color strength.

In one embodiment, the method according to the invention is characterized in that the weight ratio of cotton-containing textile material to liquor is from 1: 10 to 1:35, preferably from 1: 15 to 1:25.

Such a weight ratio has the advantage of a good flowability to the fabric material during dyeing with uniform color pickup.

In one embodiment, the method according to the invention is characterized in that the pH of the liquor is from 5.5. to 6.5.

Preferably, the pH of the liquor is from 5.0 to 6.0 during the method steps (a) and (b).

The pH may be adjusted using commonly known acids and/or bases as well as commonly known buffer substances. In one embodiment, the method according to the invention is characterized in that the amount of the at least one reactive dye in the liquor is from 0.01 to 15 wt.-%, preferably from 0.1 to 6 wt.-%, based on the total weight of the fabric.

In case more than one reactive dye is used, the amount as defined above refers to the sum of the amounts of all reactive dyes used in one embodiment.

In another embodiment, in case more than one reactive dye is used, the amount as defined above refers to the amount of each reactive dye individually.

In one embodiment, the method according to the invention is characterized in that exactly one reactive dye is present in the liquor.

In one embodiment, the method according to the invention is characterized in that more than one reactive dye is present in the liquor. Preferably, two, three or four different reactive dyes may be present in the liquor.

Hence, the dyes can be applied individually or in mixtures may be two or three dyes (di- or tri-chromicity) or else four or more dye mixtures, especially in the production of black/grey shades.

The reactive dye is not particularly limited but all reactive dyes known for the dyeing of cotton-containing textile material may be used.

In one embodiment, the method according to the invention is characterized in that the at least one reactive dye is selected from AVITERA YELLOW SE, AVITERA Red SE, AVITERA Blue SE, AVITERA Deep Blue SE, AVITERA Deep Sea SE, AVITERA Navy SE, AVITERA Orange SE, AVITERA Black SE, AVITERA Rose SE, NOVACRON Yellow S-3R, NOVACRON Yellow EC-2R, NOVACRON Bold Yellow, NOVACRON Deep Red EC-D, reactive Red 239, NOAVCRON Bold Red, NOAVRON Blue EC-R, NOVACRON Deep Blue S-DC, NOVACRON Navy S-G, NOVACRON Bold Navy, NOAVCRON Bold Deep Navy, NOVACRON Deep night S-R, NOVACRON Scarlet EC-6G, NOVACRON Ruby S-3B, NOVACRON Orange EC-3R, NOVACRON Deep Orange S-4R, NOVACRON Brown C-7R, NOVACRON Red EC-2BL, NOVACRON Red WIN, NOVACRON Navy EC-BN, NOVACRON Dark Blue S-GL, NOVACRON Super Black G, NOVACRON Super Black R and NOVACRON Black W-NN.

In one embodiment, the method according to the invention is characterized in that the cotton-containing textile material consists of cotton or comprises a cotton blend fabric. Preferred blends comprise cotton with polyester fabrics, wherein the ratio of cotton to polyester is about 25:75, preferably about 33:67, most preferred about 50: 50.

The cotton-containing textile material can be in a very wide variety of processing forms, for example in the form of fibers, yarns, woven fabrics or knitted fabrics and/or in the form of carpets.

The at least one silicone oil used in the method according to the invention is not particularly limited.

Preferably, the at least one silicone oil comprises or consist of a non-functional silicone.

Preferably, the at least one silicone oil comprises or consist of a linear silicone.

Preferably, the at least one silicone oil comprises or consist of a linear nonfunctional silicone.

Preferably, the at least one silicone oil comprises or consist of polydimethylsiloxane, preferably with a viscosity at 25 °C of 50 to 370 cPs at 50 °C (determined on a Brookfield Viscometer).

Preferably, the at least one silicone oil has a viscosity at 25 °C of 50 to 370 cPs and/or a viscosity at 50°C from 30 to 220 cPs and/or a viscosity at 70 °C from 25 to 180 cPs (determined on a Brookfield Viscometer).

Preferably, the at least one silicone oil has a boiling point above 230°C.

In one embodiment, one silicone oil is used in the process of the invention. In another embodiment, two or more than two different silicone oils (silicone oil mixture) are used in the process of the invention.

In one embodiment, the liquor may further contain a mineral oil.

The mineral oil is not restricted and can be a common mineral oil available on the market.

In one embodiment, the method according to the invention is characterized in that the weight ratio of the at least one mineral oil to water is from 1: 100 to 1:50, preferably from 1:90 to 1:70.

In one embodiment, the method according to the invention is characterized in that the weight ratio of at least one silicone oil to water is from 75:25 to 90: 10, preferably from 85: 15 to 90: 10, and the weight ratio of the at least one mineral oil to water is from 1: 100 to 1:50, preferably from 1:90 to 1:70.

The liquor may further comprise usual additives such as desizing agents, bleaching agents, wetting agents, enzymes, stabilizers, complexing agents, dispersants, anti-foams, leveling agents, penetration accelerants and pH regulators, such as buffer agents.

Such additives are usually contained in the liquor in an amount of 0.1 to 5 wt.-%, based on the weight of the liquor, each.

In one embodiment, the liquor does not contain any additives, in particular none of the before-mentioned additives.

The invention further relates to a dyed cotton-containing textile material obtained according to a method as defined above.

All definitions and preferred embodiments as set forth above apply analogously, to the dyed cotton-containing textile material. The following Examples serve to illustrate the invention. Unless otherwise indicated therein, parts are parts by weight and percentages are percentages by weight. Temperatures are given in degrees Celsius.

Examples

Example 1:

5 gm of a Cotton fabric was immersed in the water-oil liquor, containing the solution of surfactant and reactive dyes. Fiber: Liquor ratio was 1:20. The surfactant solution was added as PLURONIC PE 10100 2 g/l and AVITERA® Yellow SE (reactive Dye) was added 1% with respect to weight of fabric. Total water in the dyeing system is 15 gm and oil were 85 gm. The liquor is then stirred at 30°C for 10 min then heated at a rate of 2°C/min. to 80° C. After 25 min. at 80°C., the temperature is hold for next 20 min then cooled at a rate of 3°C/min. to 60°C. At 60°C add Sodium carbonate solution and hold for next 40 min. After that fabric was washed with Hot water twice and further processed for neutralization followed by soaping and cold wash. The medium shade was tested for fastness, and it was observed with good fastness properties is obtained.

la:

5 gm of a Cotton fabric was immersed in the water, containing the solution of auxiliary and reactive dyes. Fiber: Liquor ratio was 1: 10. The auxiliary solution was added as ALBATEX DBC (Protective colloid) 1 g/l, ALBAFLUID C (lubricant) lg/l, ALBATEX LD (leveling agent) 0.5 g/l, ALBAFLOW CIR (penetration accelerant) 1 g/l, Glauber salt 60 g/l and AVITERA® Yellow SE (reactive Dye) was added 1% with respect to weight of fabric. Total water in the dyeing system is 50 gm. The liquor is then stirred at 30°C for 10 min then heated at a rate of 2°C/min to 60° C. After 15 min. at 60°C., the temperature is hold for next 45 min then add Sodium carbonate solution and hold for next 45 min. After that fabric was washed with cold wash then processed for neutralization followed by hot wash, soaping and cold wash.

5 gm of a Cotton fabric was immersed in the water-oil liquor, containing the solution of surfactant and reactive dyes. Fiber: Liquor ratio was 1:20. The surfactant solution was added as PLURONIC PE 10100 2 g/l and AVITERA® Red SE (reactive Dye) was added 1% with respect to weight of fabric. Total water in the dyeing system is 15 gm and oil were 85 gm. The liquor is then stirred at 30°C for 10 min then heated at a rate of 2°C/min. to 80° C. After 25 min. at 80°C., the temperature is hold for next 20 min then cooled at a rate of 3°C/min. to 60°C. At 60°C add Sodium carbonate solution and hold for next 40 min. After that fabric was washed with Hot water twice and further processed for neutralization followed by soaping and cold wash. The medium shade was tested for fastness, and it was observed with good fastness properties is obtained.

Comparative Example 2a:

5 gm of a Cotton fabric was immersed in the water, containing the solution of auxiliary and reactive dyes. Fiber: Liquor ratio was 1: 10. The auxiliary solution was added as ALBATEX DBC (Protective colloid) 1 g/l, ALBAFLUID C (lubricant) lg/l, ALBATEX LD (leveling agent) 0.5 g/l, ALBAFLOW CIR (penetration accelerant) 1 g/l, Glauber salt 60 g/l and AVITERA® Red SE (reactive Dye) was added 1% with respect to weight of fabric. Total water in the dyeing system is 50 gm. The liquor is then stirred at 30°C for 10 min then heated at a rate of 2°C/min. to 60° C. After 15 min. at 60°C., the temperature is hold for next 45 min then add Sodium carbonate solution and hold for next 45 min. After that fabric was washed with cold wash then processed for neutralization followed by hot wash, soaping and cold wash.

Example 3:

5 gm of a Cotton fabric was immersed in the water-oil liquor, containing the solution of surfactant and reactive dyes. Fiber: Liquor ratio was 1:20. The surfactant solution was added as PLURONIC PE 10100 2 g/l and AVITERA® Blue SE (reactive Dye) was added 1% with respect to weight of fabric. Total water in the dyeing system is 15 gm and oil were 85 gm. The liquor is then stirred at 30°C for 10 min then heated at a rate of 2°C/min. to 80° C. After 25 min. at 80°C., the temperature is hold for next 20 min then cooled at a rate of 3°C/min. to 60°C. At 60°C add Sodium carbonate solution and hold for next 40 min. After that fabric was washed with Hot water twice and further processed for neutralization followed by soaping and cold wash. The medium shade was tested for fastness, and it was observed with good fastness properties is obtained. Comparative Example 3a:

5 gm of a Cotton fabric was immersed in the water, containing the solution of auxiliary and reactive dyes. Fiber: Liquor ratio was 1: 10. The auxiliary solution was added as ALBATEX DBC (Protective colloid) 1 g/l, ALBAFLUID C (lubricant) lg/l, ALBATEX LD (leveling agent) 0.5 g/l, ALBAFLOW CIR (penetration accelerant) 1 g/l, Glauber salt 60 g/l and AVITERA® Blue SE (reactive Dye) was added 1% with respect to weight of fabric. Total water in the dyeing system is 50 gm. The liquor is then stirred at 30°C for 10 min then heated at a rate of 2°C/min. to 60° C. After 15 min. at 60°C., the temperature is hold for next 45 min then add Sodium carbonate solution and hold for next 45 min. After that fabric was washed with cold wash then processed for neutralization followed by hot wash, soaping and cold wash.

Example 4:

5 gm of a Cotton fabric was immersed in the water-oil liquor, containing the solution of surfactant and reactive dyes. Fiber: Liquor ratio was 1:20. The surfactant solution was added as PLURONIC PE 10100 2 g/l and 1.0% AVITERA® Yellow SE, 1.0% AVITERA Red SE and 1.0% AVITERA Blue SE (reactive Dyes) was with respect to weight of fabric. Total water in the dyeing system is 15 gm and oil were 85 gm. The liquor is then stirred at 30°C for 10 min then heated at a rate of 2°C/min. to 80° C. After 25 min. at 80°C., the temperature is hold for next 20 min then cooled at a rate of 3°C/min. to 60°C. At 60°C add Sodium carbonate solution and hold for next 40 min. After that fabric was washed with Hot water twice and further processed for neutralization followed by soaping and cold wash. The medium shade was tested for fastness, and it was observed with good fastness properties is obtained.

5 gm of a Cotton fabric was immersed in the water, containing the solution of auxiliary and reactive dyes. Fiber: Liquor ratio was 1: 10. The auxiliary solution was added as ALBATEX DBC (Protective colloid) 1 g/l, ALBAFLUID C (lubricant) lg/l, ALBATEX LD (leveling agent) 0.5 g/l, ALBAFLOW CIR (penetration accelerant) 1 g/l, Glauber salt 60 g/l and 1.0% AVITERA® Yellow SE, 1.0% AVITERA Red and 1.0% AVITERA Blue SE (reactive Dyes) was with respect to weight of fabric. Total water in the dyeing system is 50 gm. The liquor is then stirred at 30°C for 10 min then heated at a rate of 2°C/min. to 60° C. After 15 min. at 60°C., the temperature is hold for next 45 min then add Sodium carbonate solution and hold for next 45 min. After that fabric was washed with cold wash then processed for neutralization followed by hot wash, soaping and cold wash.

Examples 5 to 7:

5 gm of a Cotton fabric was immersed in the water-oil liquor and mineral oil with 1.8 g/l to 7.2 g/l containing the solution of surfactant and reactive dyes. Fiber: Liquor ratio was 1:20. The surfactant solution was added as like PLURONIC PE 10100, which varies from 0.5 g/l to 3.6 g/l. and mixture of AVITERA® Gold SE, AVITERA® Red SE and AVITERA® Deep Sea SE (Reactive Dye) was added 2.65 % with respect to weight of fabric. Total water in the dyeing system is 15 gm and silicone oil is 84.82 gm and mineral oil is 0.18 gm. The liquor is then stirred at 30°C for 10 min then heated at a rate of 2°C/min. to 80 °C. After 25 min. at 80°C., the temperature is hold for next 20 min then cooled at a rate of 3°C/min. to 60°C. At 60°C add Sodium carbonate solution and hold for next 40 min. After that fabric was washed with hot water twice and further processed for neutralization followed by soaping and cold wash. The medium shade was tested for fastness, and it was observed that good fastness properties were obtained.

The ratios of silicone oil and mineral oil of Examples 5 to 7 are listed in Table 1, the balance is water:

Table 1:

The Application results for the Examples 5 to 7 are summarized in Table 2:

Table 2:

In the examples, a linear non-functional silicone oil was used.

Color and Fastness Results:

Table 3:

Light fastness was determined according to ISO 105 B02BW and the washing fastness was determined according to AATCC 61 2A (49 deg for 45 min).

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Claims

1. A method for dyeing cotton-containing textile material, wherein the textile material is treated with a liquor containing at least one reactive dye, at least one silicone oil, at least one surfactant and water.

2. Method according to claim 1, wherein the dyeing comprising the steps

(a) incubating the textile material with the liquor containing at least one reactive dye, at least one silicone oil, at least one surfactant and water,

3. Method according to claim 2, wherein the concentration of the at least one surfactant in the liquor is from 0.1 to 5.0 g/l, preferably from 2 to 4 g/l.

4. Method according to claim 2 or 3, further comprising the steps

(c) addition of alkali, preferably at a temperature which is lower than the temperature in step (b);

(d) neutralizing and washing the textile material.

5. Method according to one of the preceding claims, wherein the weight ratio of the at least one silicone oil to water is from 75:25 to 90: 10, preferably from 85: 15 to 90: 10.

6. Method according to one of the preceding claims, wherein the weight ratio of cotton-containing textile material to liquor is from 1: 10 to 1:35.

7. Method according to one of the preceding claims, wherein the amount of the at least one reactive dye in the liquor is from 0.01 to 15 wt.-% based on the total weight of the fabric.

8. Method according to one of the preceding claims, wherein the at least one reactive dye is selected from AVITERA YELLOW SE, AVITERA Red SE, AVITERA Blue SE, AVITERA Deep Blue SE, AVITERA Deep Sea SE, AVITERA Navy SE, AVITERA Orange SE, AVITERA Black SE, AVITERA Rose SE, NOVACRON Yellow S- 3R, NOVACRON Yellow EC-2R, NOVACRON Bold Yellow, NOVACRON Deep Red EC- D, reactive Red 239, NOAVCRON Bold Red, NOAVRON Blue EC-R, NOVACRON Deep Blue S-DC, NOVACRON Navy S-G, NOVACRON Bold Navy, NOAVCRON Bold Deep Navy, NOVACRON Deep night S-R, NOVACRON Scarlet EC-6G, NOVACRON Ruby S-3B, NOVACRON Orange EC-3R, NOVACRON Deep Orange S-4R, NOVACRON Brown C-7R, NOVACRON Red EC-2BL, NOVACRON Red WIN, NOVACRON Navy EC-BN, NOVACRON Dark Blue S-GL, NOVACRON Super Black G, NOVACRON Super Black R and NOVACRON Black W-NN.

9. Method according to one of the preceding claims, wherein the liquor further contains a mineral oil.

10. Method according to one of the preceding claims, wherein the weight ratio of the at least one mineral oil to water is from 1: 100 to 1: 50, preferably from 1:90 to 1:70.

11. Method according to one of the preceding claims, wherein the cottoncontaining textile material consists of cotton or comprises a cotton blend fabric; preferably wherein cotton is blended with polyester fabrics.

12. The dyed cotton-containing textile material obtained according to a method of any of claims 1 to 11.